Writing instrument



United States Patent 3,261,326 WRITING INSTRUMENT Robert G. Ryan, .lanesville, Wis., assignor to The Parker Pen Company, .lanesville, Wis, a corporation of Wisconsin Continuation of application Ser. No. 101,554, Apr. 7, 1961. This application Feb. 7, 1964, Ser. No. 344,164 Claims. (Cl. 120--42.4)

The present invention relates in general to writing instruments of the ball pen type and more particularly to the ball and ball seat portions of a ball point writing instrument. This is a continuation of application Serial No. 101,554, filed April 7, 1961, now abandoned.

Writing instruments of the type which utilize a rotatable ball for inscribing a line of ink on a writing surface are known, at the present time, as ball point pens or pencils, depending upon the type of writing media which they employ. These writing instruments include a reservoir in which a supply of ink is stored, a socket or seat which communicates with the reservoir, and a writing ball which is rotatably held in the socket and which, when dragged across the writing surface, is caused to roll whereby the back or inner portion thereof transfers ink from the rear portion of the socket outwardly of the socket whereby the ink is laid out on the writing surface. In order for the ball to rotate within the socket it is necessary to provide clearance between the ball and the ad jacent parts of the socket but the amount of clearance which is provided must not be so great as to cause an undesirably large amount of ink to be transferred from the reservoir to the writing surface as the ball rotates. In accordance with the teachings of the prior art, the sockets of present-day ball point writing instruments include an annular space or groove disposed rearwardly of the equator of the ball which is connected by suitable means such as channels to the reservoir so as to remain relatively full of ink at all times. This space may be suitably called an equalizer groove, since it functions to equally bathe the rearward surface of the ball with ink and it also serves to distribute air which is returned to the socket as the ball is rotated during writing. Forwardly of the equalizer groove the socket conforms relatively closely to the adjoining surface of the ball and the clearance which is provided between the ball and the socket in this location determines the rate at which ink is removed from the reservoir as the ball rotates. This portion of the socket thus removes or doctors a portion of the ink which adheres to the ball as it rotates through the equalizer space.

As the ball rotates across a writing surface, there is a substantial portion of the ball which is disposed outside of the socket but which does not engage the writing surface so that ink is not removed from that latter portion of the ball which does not contact the writing surface. Consequently, unless this ink which remains on the ball as it re-enters the socket passes into the socket, it collects at the lip of the socket, thereby forming a small globule of ink which, when the direction of rotation of the ball is reversed, causes an abnormally large deposit of ink on the writing surface. This is a common characteristic of present-day ball point pens and is generally referred to as gooping. Since the ink is doctored from the ball in the prior art types of sockets in the immediate vicinity of the lip of the socket, an extremely close tolerance must be provided at that point and accordingly, the tendency of the ink not to return into the socket results in the formation of the globule of ink and the consequent gooping.

Therefore, a principal object of the present invention is to provide a new and improved ball point writing instrument.

3,251,325 Patented July 19, 1966 Another object of the present invention is to provide a new and improved seat for a ball point writing instrument.

Still another object of the present invention is to provide a new and improved ball point writing instrument in which uniformity of the writing line is maintained.

A further object of the present invention is to provide a new and improved seat which eliminates gooping.

A still further object of the present invention is to provide a new and improved ball seat in which accurate control of the rate of ink transfer from the reservoir is obtained.

Briefly, the above and further objects are realized in accordance with the present invention by providing a ball point writing instrument including a ball socket having a rearwardly disposed seat against which the ball is forced during normal use of the instrument, an equalizer groove disposed forwardly of the seat, a metering ring disposed forwardly of the equalizer groove for controlling the rate of ink transferred from the reservoir to the ball during writing, an annular collector groove disposed forwardly of the metering ring and a lip disposed forwardly of the ball for holding the ball within the socket.

Further objects and advantages and a better understanding of the present invention may be had by reference to the following detailed description taken in connection with the accompanying drawings in which:

FIG. 1 is a longitudinal, sectional view taken along the center line of a writing instrument embodying the present invention;

FIG. 2 is a sectional view taken along the line 22 in FIG. 1, assuming the entire structure to be shown therein;

FIG. 3 is a fragmentary view, partly in section, of the tip of a ball point writing instrument embodying the present invention during manufacture thereof prior to the time the lip is turned over the ball to hold it in place; and

FIG. 4 is an end view of a ball point writing instrument embodying the present invention, illustrating the manner in which ink is removed from the ball by the writing surface during writing.

Referring now to the drawings and particularly to FIG. 1 thereof, there is shown a tip 10 of a ball point writing instrument embodying the present invention. The tip 10 comprises a writing ball 11 which is substantially spherical in shape and which is rotatably journalled in a socket 12. A cylindrical feed channel 13 connects to the rear or upper portion of the socket 12 and conveys ink from an associated reservoir (not shown) to the socket 12 and to the ball 11 for transfer to a writing surface. FIG. 3 is similar to FIG. 1 and illustrates a tip 10 prior to the deformation of the lower portion or rim of the socket to rotatably secure the ball 11 in place and FIG. 3 thus illustrates the manner in which the tip may be assembled and completed.

As best shown in FIG. 2, the socket 12 comprises a rearwardly disposed seat portion formed by a plurality of arcuately shaped lands 15 which are respectively spaced apart by a plurality of fissures or grooves 16 which connect the feed channel 13 with an equalizer space or groove 18. Normally, the ball 11 has a diameter of approximately one millimeter and therefore, the grooves 16 are necessarily extremely narrow. As the width of the grooves 16 is increased, the area of the lands 15 must decrease with a consequent increase in the wearing away of the seat during use of the ball. Since these dimensions are thus interrelated, it is desirable to select the relative dimensions of the lands area 15 and the grooved area 16 to provide a sufiicient flow of ink from the feed channel 13 to the equalizer groove 18 to prevent starving of the ball while providing a socket in which excessive wear of the seat will not result. If excessive wear were to result,

excessive play of the ball would occur with a consequent excessive rate of ink flow onto the writing surface.

As the ball 11 rotates in the socket 12, ink adheres to the rearward surface of the ball, particularly in the vicinity of the equalizer space 13, and is moved forwardly out of the socket and onto the Writing surface by the ball. In order to accurately control the amount of ink which is thus picked up by the ball from the groove 18, there is provided in accordance with the present invention a ring 20 having an annular ball engaging surface closely conforming to the adjacent portion of the ball 11. The ciearance between the ball 11 and the ring 26 determines the thickness of the layer of ink which is transferred forwardly of the equalizer groove 18 by the rotating ball 11. The layer of ink which thus adheres to the portion of the ball rotating forwardly past the ring 20 passes out of the socket 12 and is deposited on a Writing surface 22 such, for example, as a sheet of paper, shown in cross-section in FIG. 1. The greater the clearance between the ball and the ring 20, the greater is the amount of ink written out on the paper.

As shown in FIG. 4, as the ball 11 traverses a straight line along a writing surface, a band of ink is removed from the center portion of the ball periphery, leaving a central surface 24 which is relatively free of ink. However, the side portions 25 and 26 of the ball retain the original amount of ink thereon. These ink layers on the ball portions 25 and 26 return to the socket and feed into an annular collector groove 28 which is disposed forwardly of the metering ring 20. Under normal circumstances, the collector groove 28 is only partially filled with ink, since the portion of the ball which is rotating out of the socket carries ink from the groove 28 with it. Of course, additional ink is being carried into the ring 28 by the portion of the ball rotating from the equalizer groove 18 but if the collector groove 28 is filled with ink at the location of that part of the ball which is rotating therein from the equalizer groove 18, there is no place for the ink to be transferred and hence it remains in the equalizer groove 18. However, the opposite side of the collector groove 28 is not normally filled with ink and, therefore, the ink being returned by the ball from the side sections 25 and 26 of the ball, as shown in FIG. 4, may move into the socket and into this space within the collector groove 28 whereby such returned ink floors around through the groove 28 to the portion of the ball which is rotating outwardly of the socket. Should the direction of rotation of the ball 11 be changed before such transfer of returned ink takes place, that returned ink is moved directly out of the socket by the ball. Another advantage of the collector groove 28 is that abrupt changes in the direction of rotation of the ball 11, as is caused by reversal of direction of movement of the pen on the paper, do not result in a diminution of the quantity of ink momentarily written out on the paper since the collector ring 28 functions to main the fonward parts of the ball bathed with ink.

One method of manufacturing the ball tip 10 is to drill the feed channel 13 in the housing and thereafter counterbore the housing to provide the grooves 18 and 28. The feed grooves 16 may then be punched and the ball 11 may be coined in place to conform the lands 15 and the ring 20 to the ball surface. Thereafter, the forward portion of the tip may be spun over the ball to the condition shown in FIG. 1 to secure the ball 11 in place, care being maintained that the collector groove 28 is not destroyed during spinning.

While the present invention has been described in connection with a particular embodiment thereof, it will be understood that many changes and modifications may be made without departing from the true spirit and scope of the invention and, therefore, it is intended by the appended claims to cover all such changes and modifications which come within the true spirit and scope of the invention.

What is claimed is:

1. In a device of the character described including a writing ball, a ball setting for rotatably mounting said ball, and an ink reservoir, said ball setting comprising a socket for reception of said ball, a feed channel opening into said cocket for supplying ink from said reservoir to said ball, an annular shoulder disposed rearwardly of the equator of said ball, said shoulder having a substantial annular defining a portion of a sphere, said annular surface being adapted to engage With said ball throughout a continuous annular area, a rim integral with said socket and disposed only forwardly of the equator of said ball to retain said ball in said socket, structure means defining an annular cavity surrounding said ball throughout an area spanning the equator of said ball between said annular shoulder and said rim, a plurality of spherical land surfaces spaced rearwardly from said annular shoulder and spaced mutually apart by radial fissures opening into said feed channel and an annular groove disposed rearwardly of said annular shoulder between said annular shoulder and said land surfaces, said fissures connecting said feed channel with said groove.

2. In a device of the character described, the combination of a single socket forming member, a ball rotatably mounted in the socket of said member, means defining a feed channel in said member for supplying ink fro-m a reservoir to the socket, an annular ink metering shoulder disposed rearwardly of the equator of said ball and in engagement with said ball throughout a continuous area of constant forward to rearward dimension encircling said ball, a lip integral with and at the forward end of said member partly turned over said ball and adapted to engage said ball through a narrow annular area only forward of said equator for retaining said ball in said socket, means forming an annular cavity surrounding said ball and dis posed between said annular shoulder and said lip, said cavity having a front-to-rear dimension substantially greater than the corresponding dimension of said lip to provide a space of substantial volume for receiving ink from the surface portion of said ball entering said socket past said lip, means forming a second annular cavity in said socket disposed reaiwvardly of said annular shoulder in communication therewith, and a plurality of feed passageways connected between said feed channel and said second annular cavity.

3. A writing instrument comprising a unitary structure forming a socket for reception of a writing ball and a feed channel for supplying ink from a reservoir to said ball, a narrow annular shoulder of uniform width disposed rearwardly of the equator of said ball providing a controlled clearance between said shoulder and said ball, a lip disposed forwardly of the equator of said ball for retaining said ball in said socket, a rear seat surface rearwardly of said annular shoulder and comprising a plurality of land surfaces spaced mutually apart by radial fissures, an annular cavity surrounding said ball forwardly of said annular shoulder throughout a band of substantial width spanning the equator of said ball, and a second annular cavity disposed rearwardly of said annular shoulder in communication with said feed channel through the fissures separating the rear seat land surfaces.

4. In a device of the character described including a writing ball, a ball setting for rotatably mounting said ball, and an ink reservoir, said ball setting comprising the combination of a single member forming a socket for reception of said ball including a feed channel opening onto said ball for conveying ink from said reservoir to the ball, a plurality of land means disposed in the rear portion of said socket for seating said ball, said land means being spaced apart to provide fissures communicating said feed channel to a location forward of said land means, a narrow annular shoulder disposed rearwardly of the equator of said ball forwardly of said land means in engagement with said ball throughout a continuous, generally spherical area encircling said ball, a lip integral with said member disposed only forwardly of the equator of said ball in engagement with said ball for retaining said ball in said socket, said member forming a first annular cavity of substantial forward to rearward length surrounding said ball between said annular shoulder and said lip, and means defining a second annular cavity between said shoulder and said land means.

5. The combination of means defining a socket, a ball journalled in said socket with a substantial portion of said ball protruding therefrom, means defining .an ink feed 10 channel for interconnecting an ink reservoir and said 'ball, a seat in said socket disposed rearwardly of the equator of said ball for preventing substantial rearward movement of said ball in said socket, a rim integral with said socket means for preventing substantial forward movement of said ball in said socket, an annular metering shoulder disposed between said rim and said seat, an equalizer groove disposed between said seat and said shoulder, said seat being interrupted by a plurality of angul-arly spaced, radially extending fissures intercommunicating said equalizer groove with said ink feed channel, and an annular collector groove disposed between said shoulder and said rim.

References Cited by the Examiner UNITED STATES PATENTS 2,847,975 8/ 1958 LEllWtOl'l l20--4-2.4 2,967,353 1/1961 Arengo 12-0-42.4

FOREIGN PATENTS 566,730 12/ 1958 Canada. 814,734 6/ 1959 Great Britain.

15 EUGENE R. CAPOZIO, Primary Examiner.

JEROME SCI-I-NALL, Examiner.

E. HOROWITZ, HERBERT ROSS, Assistant Examiners. 

3. A WRITING INSTRUMENT COMPRISING A UNITARY STRUCTURE FORMING A SOCKET FOR RECEPTION OF A WRITING BALL AND A FEED CHANNEL FOR SUPPLYING INK FROM A RESERVOIR TO SAID BALL, A NARROW ANNULAR SHOULDER OF UNIFORM WIDTH DISPOSED REARWARDLY OF THE EQUATOR OF SAID BALL PROVIDING A CONTROLLED CLEARANCE BETWEEN SAID SHOULDER AND SAID BALL, A LIP DISPOSED FORWARDLY OF THE EQUATOR OF SAID BALL FOR RETAINING SAID BALL IN SAID SOCKET, A REAR SEAT SURFACE REARWARDLY OF SAID ANNULAR SHOULDER AND COMPRISING A PLURALITY OF LAND SURFACES SPACED MUTUALLY APART BY RADIAL FISSURES, AN ANNULAR CAVITY SURROUNDING SAID BALL FORWARDLY OF SAID ANNULAR SHOULDER THROUGHOUT A BAND OF SUBSTANTIAL WIDTH SPANNING THE EQUATOR OF SAID BALL, AND A SECOND ANNULAR CAVITY DISPOSED REARWARDLY OF SAID ANNULAR SHOULDDER IN COMMUNICATION WITH SAID FEED CHANNEL THROUGH THE FISSURES SEPARATING THE REAR SEAT LAND SURFACES. 